As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TAXI OUT, THE RIGHT ENGINE WAS REPORTED BY A FOLLOWING AIRCRAFT TO HAVE SPARKS EXITING THE TAIL OF THE ENGINE. CREW SHUTDOWN THE RIGHT ENGINE AND RETURNED TO GATE. MAINTENANCE REPLACED THE RIGHT ENGINE. ENGINE OPERATIONAL CHECK OK. AIRCRAFT RETURNED TO SERVICE.